Aerobic organism

Aerobic organism
Aerobic and anaerobic bacteria can be identified by growing them in a liquid culture:
1: Obligate aerobic bacteria gather at the top of the test tube in order to absorb maximal amount of oxygen.
2: Obligate anaerobic bacteria gather at the bottom to avoid oxygen.
3: Facultative bacteria gather mostly at the top, since aerobic respiration is the most beneficial one; but as lack of oxygen does not hurt them, they can be found all along the test tube.
4: Microaerophiles gather at the upper part of the test tube but not at the top. They require oxygen but at a low concentration.
5: Aerotolerant bacteria are not affected at all by oxygen, and they are evenly spread along the test tube.

An aerobic organism or aerobe is an organism that can survive and grow in an oxygenated environment.[1] Faculitative anaerobes grow and survive in an oxygenated environment and so do aerotolerant anaerobes.

Contents

Glucose

A good example would be the oxidation of glucose (a monosaccharide) in aerobic respiration.

C6H12O6 + 6 O2 + 38 ADP + 38 phosphate → 6 CO2 + 6 H2O + 38 ATP

Notice that oxygen is used during the oxidation of glucose and water is produced.

This equation is a summary of what actually happens in three series of biochemical reactions: glycolysis, the Krebs cycle, and oxidative phosphorylation.

Diversity

Almost all animals, most fungi, and several bacteria are obligate aerobes, which require oxygen. Most anaerobic organisms are bacteria.[clarification needed] Being an obligate aerobe, although advantageous from the energetical point of view, also means obligatory exposure to high levels of oxidative stress.

Yeast is an example of a facultative anaerobe, which can develop in the presence of oxygen but does not require it. Individual human cells are also facultative anaerobes: they switch to lactic acid fermentation if oxygen is not available. However, for the whole organism this cannot be sustained for long, and humans are therefore obligate aerobes.

References

  1. ^ "aerobe" at Dorland's Medical Dictionary

See also


Wikimedia Foundation. 2010.

Игры ⚽ Нужен реферат?

Look at other dictionaries:

  • Aerobic — is an adjective that means requiring air , where air usually means oxygen.Aerobic may also refer to: * Aerobic exercise, exercise of moderate intensity * Aerobics, a form of aerobic exercise * Aerobic respiration, the aerobic process of cellular… …   Wikipedia

  • organism — Synonyms and related words: aerobic organism, an existence, anaerobic organism, anatomy, architectonics, architecture, arrangement, autotrophic organism, being, body, build, building, composition, conformation, constitution, construction,… …   Moby Thesaurus

  • Anaerobic organism — Aerobic and anaerobic bacteria can be identified by growing them in liquid culture: 1: Obligate aerobic (oxygen needing) bacteria gather at the top of the test tube in order to absorb maximal amount of oxygen. 2: Obligate anaerobic bacteria… …   Wikipedia

  • Organism — life on Earth redirects here. For the BBC series, see Life on Earth (TV series). Life on Earth Temporal range: Archaean or earlier – Recent These Escherichia coli cells provide an example of a prokaryotic microorganism …   Wikipedia

  • aerobic — aerobically, adv. /air roh bik/, adj. 1. (of an organism or tissue) requiring the presence of air or free oxygen for life. 2. pertaining to or caused by the presence of oxygen. 3. of or utilizing the principles of aerobics: aerobic exercises;… …   Universalium

  • aerobic — aer•o•bic [[t]ɛəˈroʊ bɪk[/t]] adj. 1) ecl (of an organism or tissue) requiring the presence of air or free oxygen to sustain life 2) pertaining to or caused by the presence of oxygen 3) of or pertaining to aerobics: aerobic dancing[/ex] •… …   From formal English to slang

  • Facultative anaerobic organism — A facultative anaerobic organism is an organism, usually a bacterium, that makes ATP by aerobic respiration if oxygen is present but is also capable of switching to fermentation. In contrast, obligate anaerobes die in presence of oxygen.Some… …   Wikipedia

  • Microaerophile — Aerobic and anaerobic bacteria can be identified by growing them in liquid culture: 1: Obligate aerobic (oxygen needing) bacteria gather at the top of the test tube in order to absorb maximal amount of oxygen. 2: Obligate anaerobic bacteria… …   Wikipedia

  • Obligate aerobe — Aerobic and anaerobic bacteria can be identified by growing them in liquid culture: 1. Obligate aerobe 2. Obligate anaerobe 3. Facultative anaerobic organism (continuum with Facultative aerobic organism ) 4. Microaerophile 5. Aerotolerant An… …   Wikipedia

  • Obligate anaerobe — Aerobic and anaerobic bacteria can be identified by growing them in liquid culture: 1. Obligate aerobe 2. Obligate anaerobe 3. Facultative anaerobic organism (continuum with Facultative aerobic organism ) 4. Microaerophile 5. Aerotolerant… …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”